From: Kirk, Benjamin (JSCEG311) <benjamin.kirk@na...>  20130727 11:45:57

On Jul 27, 2013, at 1:47 AM, "Derek Gaston" <friedmud@...> wrote: > Ben: is there anything that can be done here? We were really looking > forward to this... So the petsc matrices assume a constant blocking factor for the entire matrix, which I think is the bug fundamental driver here. If you solved decoupled flow/temperature in 1 matrix with equal order basis functions you'd have 4 fully coupled variables in 3D, with 1 tagalog. I don't think petsc will optimize for that case, and in fact you *might* be better memory wise splitting into two matrices where the flow vars could be coupled. Is there another use case with nonfull dof coupling I could be overlooking? I'd be happy to try to address it... Ben 